Valve and level gauge operating mechanism for liquefied gas dispensing systems



Oct 1940' J. WHlTE VALVE AND LEVEL GAUGE OPERATING MECHANISM FOR LIQUEFIED GAS DISPENSING SYSTEMS Original Filed NOV. 27. 1937 Patented Oct. 8, 1940 PATENT OFFICE VALVE AND LEVEL GAUGE OPERATING MECHANISM FOR LIQUEFIED GAS DIS- PENSING SYSTEMS Loyd J. White, San Antonio, Tex., assignor to Southern Steel Company, a corporation of Texas Application November 27, 1937, Serial No. 176,842

Renewed April 13, 1939 a 13 Claims.

This invention relates to liquefied gas storage and dispensing systems and, among other objects, aims to provide improved apparatus associated with an underground pressure storage tank to permit normal fiow of gas from the tank and to prevent the escape of gas from the tank when the upper valve and gauge fittings are broken or removed for repairs or when the gas delivering conduit on the tank is broken off. The main idea is to provide automatic valves associated with a stand-pipe extending into the pressure storage tank to permit the tank to be refueled and also serving to prevent the escape of gas from the tank when the usual control appurtenances and/ or valve fittings are removed and/or repaired or replaced. A further aim is to provide an improved fioat control in the standpipe for operating the usual level gauge. A still further aim is to provide a safety relief valve within the tank connected to the standpipe to comply with the most rigid safety requirements, preventing the possibility of excessive pressure being built up in the tank while the appurtenances are disconnected.

This application involves improvements on the systems disclosed in my copending applications Ser. No. 98,048, filed August 26, 1936, now matured into Patent No. 2,121,673, issued June 21, 1938, and Ser. No. 169,699, filed October 18, 1937, now matured into Patent No. 2,121,675, issued June 21, 1938, as well as Patent No. 2,098,119, issued November 2, 1937.

Other aims and advantages of the invention will appear in the specification, when considered in connection with the accompanying drawing,

wherein:

Fig. 1 is a central sectional view of a system embodying the invention;

Fig. 2 is an enlarged fragmentary sectional view taken on the line 2--2 of Fig. l; and

Fig. 3 is a sectional view taken on the line 3-3 of Fig. 2.

Referring particularly to the drawing, the system there shown is similar to the one disclosed in my aforesaid copending application Ser. No.

169,699 wherein a storage tank I0 is adapted to be buried in the ground and partially filled with liquefied petroleum gas. The tank is shown as having a standpipe l I connected toit and a single combination valve and gauge assembly or fitting l2 like the one shown in the said copending application is removably mounted on the top of the standpipe. As disclosed in said copending application, the fitting carries filling and vapor return valves, excess flow check valves, a Safety relief valve, a manual cutoff valve, a pressure gauge and a magnetic level gauge. The level gauge is mounted in a hollow boss l3 directly above the standpipe. The fitting also has a gas delivering nipple or extension "which is connected by pipe fittings to the usual pressure reducing regulator l4 from which the low pressure gas is delivered to a service pipe I5.

As explained in both of the aforesaid copend ing applications, the tank is adapted to be serviced or filled through the single standpipe to avoid the necessity of connecting two or more, pipes to the tank and the resulting danger of producing leaky joints. Incidentally, the vapor return fitting communicates with a dip pipe [6 which extends downwardly into the tank to approximately the maximum liquid level to prevent overfilling the tank.

In such systems, it is sometimes necessary to remove and repair or replace some of the fittings or appliances. Heretofore, it has been necessary to empty the tank of gas before any of the fittings connected to the standpipe could be safely removed. This invention provides automatic valve means associated with the standpipe within the tank to permit such repairs without the necessity of emptying the tank, serving to prevent the escape of .gas within the tank while the fittings are removed, but permitting the normal flow of gas when the system is functioning. Also, the idea is to prevent the escape of gas in the event that the valved fitting on the standpipe is broken or develops major leaks. In view of the fact that the standpipe carries azdip pipe and level gauge operating shaft, it is impossible to provide a hand cut oil valve between the tank and the combination valved fitting. Moreover, safety regulations forbid installations of any kind of hand valve between the storage tank and the pressure relief valve which, in this instance, is carried by the fitting l2.

Referring to Figs. 1 and 2, the standpipe II is shown as extending into the ,tank to a point near the bottom and has a closed lower end. It is preferably welded in the tank but may have an ordinary welded-on boiler flange to permit it to be inserted through a larger opening with the valve'attachments already assembled on it. Near the bottom of the tank at the lower end portion of the standpipe, there is shown a simple type of excess fiow check valve in the form of a screw threaded casing ll extending laterally from the standpipe and carrying a springurged ball valve l8 opening outwardly from standpipe II. T e ball valve has an ordinary spring retainer in the outer or right hand end of the casing l1 and is adapted to be seated against atapered seat at the inner end of the ball compartment of the casing, as viewed in Fig. 2. This valve is arranged to permit liquefied gas delivered through the filling valve on the fitting l2 to enter the tank through the standpipe and is adapted to close automatically due to the pressure in the tank when the fitting I2 is, disconnected from the standpipe. It is normally held open by its spring to permit liquefied gas to fiow from the tank into the standpipe and establish its level therein when the fitting I2 is in place and the pressure in the standpipe is the same as that in the tank. It is contemplated that an ordinary check valve may be adapted to serve these purposes. Within the upper portion of the tank is another excess fiow check valve having a casing I9 similarly connected to the standpipe and carrying a spring urged ball valve 20, also opening outwardly from the standpipe ll into the tank ill, to permit the normal flow of gas or vapor therethrough from the tank into the standpipe. When the flow becomes excessive for any reason, this valve will close automatically. It will close and remain closed when the fitting I2 is disconnected from the standpipe due to the pressure in the tank. It is arranged to permit the normal fiow of gas to the service pipe l5 even while the tank is being filled and vapor is also passing out through the dip pipe 16. Incidentally, this valve permits slight leakage of gas, having a slightly roughened or hair scratched seat to permit enough gas to fiow from the tank into the standpipe to reestablish the pressure in the standpipe after the fitting at the top of the standpipe is replaced and thereby cause both valves to open. The lower valve then permits: the liquefied gas in the tank to flow through it and establish its lev within the standpipe.

Inasmuch as it is necessary to close the standpipe from any communication with the tank to prevent the gas from escaping through it to the atmosphere when the combination fitting is removed, ordinary floats for operating the level gauge cannot be employed. In this example, a non-circular -fioat operating rod or shaft 2| extends downwardly into the standpipe having a bearing 22 in its lower end wall or closure. It is shown as being spirally twisted through a partial revolution to operate the hand of the level gauge. It carries a slidably mounted fioat 23 also within the standpipe and guided in its rising and falling movement by a pair of guide rods 24 projecting downwardly from the fitting and the level gauge housing to the bottom closure of the standpipe. The float is shown as having a square opening engaging the gauge operating rod 20 to impart rotating movement to it as the float rises and falls.

To comply with safety regulations, the standpipe is also shown as carrying a safety relief valve within the tank to prevent excessive pressure from developing within the tank while the combination fitting is removed. Herein, an ordinary safety relief valve in the form of a screw threaded nipple or casing 25 carrying a valve 26 is shown as being connected to the standpipe opposite the vapor excess fiow check valve casing l9. It is arranged to open inwardly or toward the standpipe to permit gas to escape through the standpipe when excessive pressure develops in the tank.

It will be understood that the pressure within the tank will serve to close both excess flow Ch k valves when the fitting or the dispensing appliances are disconnected from the standpipe and the safety relief valve will likewise remain normally closed. When the tank is partially filled with liquefied gas, some of it will be trapped within the standpipe. It will vaporize quickly and escape into the atmosphere through the open standpipe. Then, no more gas can escape from the tank until the fitting or appliances are replaced and the pressure in the'standpipe is equalized with that in the tank.

From the foregoing description, it will be understood that the safety valve appliances and the improved gauge operating means can be installed very easily at a relatively low cost. The valves may assume a great variety of forms and may even be installed so that they are fiush with the outer wall of the standpipe to permit insertion of the standpipe through a small opening in the tank wall. However, they may be installed in the standpipe after it is welded on the tank and before one or both of the tank heads are welded on.

Obviously, the present invention is not restricted to the particular embodiment thereof herein shown and described. Moreover, it is not indispensible that all the features of the invention be used conjointly, since they may be employed advantageously in various combinations and sub-combinations.

What is claimed is:

1. In a liquefied gas storage and dispensin system of the class described, a storage tank; a standpipe connected to and extending within the tank; dispensing appurtenances including a valved fitting removably connected to the upper end of the standpipe; and automatic valve means connected to the standpipe within and near the top and bottom of the tank permitting gas to be delivered through the standpipe, but preventing escape of-gas from the tank to the atmosphere when said valved fitting is removed or when the standpipe is broken outside the tank.

2. In a liquefied gas storage and dispensing system of the class described, a storage tank; a standpipe connected to and extending within the tank; filling and dispensing appurtenances including a valved fitting removably connected to the upper end of the standpipe; and excess flow check valves connected to the standpipe within and opening into the tank permitting the tank to be filled through the standpipe and normal fiow of gas to be delivered from the tank through the standpipe, but preventing escape of gas from the tank to the atmosphere when said valved fitting is removed or when the standpipe is broken outside the tank.

3. In a liquefied gas storage and dispensing system of the class described, a storage tank; a standpipe connected to and extending within the tank; filling and dispensing appurtenances including a valved fitting removably connected to the upper end of the standpipe; excess flow check valves connected to the standpipe within and opening into the tank permitting the tank to be filled through the standpipe and a normal flow of gas to be delivered from the tank through the standpipe, but preventing escape of gas from the tank to the atmosphere when said valved fitting is removed; and a liquid level gauge operating means confined within said standpipe.

4. In a liquefied gas storage and dispensing system of the class described, a storage tank; a standpipe connected to and extending within the tank; filling and dispensing appurtenances including a valved fitting removably connected to the upper end of the standpipe; excess flow check valves connected to the standpipe within and opening into the tank permitting the tank to be filled through the standpipe and a normal fiow of gas to be delivered from the tank through the standpipe, but preventing escape of gas from the tank to the atmosphere when said valved fitting is removed; a spirally twisted liquid level gauge operating shaft within the standpipe; and a fioaif also confined within the standpipe slidably and non-rotatably connected to said shaft.

5. In a liquefied gas storage and dispensing system of the class described, a storage tank; a standpipe connected to and extending within the tank; filling and dispensing appurtenances including a valved fitting removably connected to the upper end of the standpipe; excess fiow check valves connected to the standpipe within and opening into the tank permitting the tank to be filled through the standpipe and a normal fiow of gas to be delivered from the tank through the standpipe, but preventing escape of gas from the tank to the atmosphere when said valved fitting is removed; and a safety relief valve opening from the tank into the standpipe preventing excessive pressure from developing in the tank while said valved fitting is disconnected.

6. In a liquefied gas storage and dispensing system of the class described, a tank; a standpipe having a closed lower end extending to the bottom portion of the tank; dispensing appurtenances removably connected to the upper end portion of the standpipe; a check valve connected to the lower end portion of the standpipe and opening outwardly into the tank permitting the tank to be filled through the standpipe; an excess flow check valve also connected to the standpipe within the upper portion of the tank permitting normal fiow of gas from the tank into the standpipe, both of said valves closing auto-' matically when the dispensing appurtenances are removed from the standpipe and thereby preventing the escape of gas from the tank to the atmosphere.

'7. In a liquefied gas storage and dispens system of the class described, a tank; a standpipe connected to and extending into the bottom portion of the tank; a fitting carrying a liquid level gauge removably secured to the upper end of the standpipe; a fioat and a gauge operating shaft confined within the standpipe; and check valves connected to the standpipe within the tank to prevent the escape of gas from the tank when the fitting is removed.

8. Ina liquefied gas storage and dispensing system of the class described, a storage tank; a

standpipe connected to and extending within the tank; dispensing appurtenances including a valved fitting removably connected to the upper end of the standpipe; automatic valve means connected to the standpipe within and near the top and bottom of the tank permitting gas to be delivered through the standpipe, but preventing escape of gas from the tank to the atmosphere when said valved fitting is removed or when the standpipe is broken outside the tank; and a liquid level gauge operating means confined within said standpipe.

9. In a liquefied gas storage and dispensing system of the class described, a storage tank; a

vertical conduit secured to the upper wall of the tank and having a closed lower end extending to a point near the bottom; dispensing appurtenances connected to communicate with the upper end of the conduit; and automatic valve means connected to the conduit within and near the top and bottom of the tank permitting gas to be delivered through the conduit but preventing escape of gas from the tank to the atmosphere when communication betweensaid appurtenances and said conduit is broken or when said appurtenances are removed, said valve means also serving to equalize the liquid level in the conduit with that in the tank.

-10. In a liquefied gas storage and dispensing system of the class described, a storage tank; a vertical conduit secured to the upper wall of the tank and having a closed lower end extending to a point near the bottom; a fitting carrying a liquid level gauge removably secured to the upper end of the conduit; a float and a gauge operating shaft confined within the conduit; and check valves connected to the conduit within the tank to prevent the escape of gas from the tank when the fitting is removed.

11. In a liquefied gas storage and dispensing system, a pressure storage tank; a vertical conduit in the tank having a closed lower and near the bottom of the tank; filling and dispensing appurtenances above the tank connected to communicate with the upper end of the conduit; automatic valve means connected to the conduit within and near the top and bottom of the tank permitting a normal flow of gas to be delivered through the conduit but preventing escape oi. gas from the tank to the atmosphere when communication between said appurtenances of said conduit is broken; and a liquid level gauge operating means confined within said conduit.

12. In a liquefied gas storage and dispensing system, a pressure storage tank; a vertical conduit in the tank having a closed lower end near the bottom of the tank; filling and dispensing appurtenances including a valved fitting above the tank removably connected to the upper end of the conduit; excess flow check valves connected to the conduit within and opening. into the tank permitting the tank to be filled through the conduit and a normal flow of gas to be delivered from the tank through the conduit but preventing escape of gas from the tank to the atmosphere when said valved fitting is removed; and a safety relief valve opening from the tank into the conduit preventing excessive pressure from developing in the tank while said valved fitting is disconnected.

13. In a liquefied gas dispensing system of the class described, a storage tank; a standpipe extending into the tank to a point near the bottom and communicating therewith to permit liquefied gas to enter its lower end and be vaporized therein to supply the gas demand; an opening in the standpipe within the tank above the maximum liquid level permitting gas to flow freely into the standpipe under normal operating conditions and thereby maintain the pressure and the liquid level in the standpipe substantially the same as that in the tank; and gas dispensing and control appurtenances connected to the standpipe.

LOYD J. warm. 9 

